A solid-state image pickup device having a reduced signal transfer time and a signal processing method using the solid-state image pickup device. A pixel array includes a plurality of light-receiving pixel elements and a plurality of light-blocked pixel elements. A read block reads the output signals of the plurality of light-blocked pixel elements. An AD conversion processing block includes a circuit for summing up the output signals of adjacent light-blocked pixel elements and transferring the signals of the light-blocked pixel elements in a reduced period.